The absence of changes in glycemia in 12‐ and 18‐month‐old female rats may be related to the high concentration of PRL, as it has been reported that chronic moderate hyperprolactinemia is associated with increased release of insulin induced by a glucose load (Fleenor & Freemark, 2001; Reis et al., 1997). This evidence concerns the gene INS and hyperprolactinemia.